Optical disc recording/reproduction apparatus having a lens group, focus, servo, and jog mode adjustment

Abstract

The present invention provides an optical disc recording/reproduction apparatus and method capable of carrying out an accurate recording or reproduction when using a lens unit consisting of at least two lenses, which comprises: first drive means for driving both of the first lenses and the second lens in a focusing direction; second drive means for relatively driving the second lens with respect to the first lens in the focusing direction; focus servo means for carrying out focus servo by driving the first drive means so as to drive both of the first lens and the second lens in the focusing direction; and jog mode adjustment means for driving the second drive means after the focus servo is locked, so as to carry out a jog mode adjustment of the position of the second lens with respect to the first lens.

What is claimed is:  
     
       1. An optical disc recording/reproduction apparatus for recording or reproducing a data by applying a beam to an optical disc via a lens group consisting of at least a first lens and a second lens, said apparatus comprising: 
       first drive means for simultaneously moving both of said first lens and said second lens in a focusing direction;  
       second drive means for moving said second lens relative to said first lens in the focusing direction;  
       focus servo means for carrying out focus servo by moving said first drive means so as to drive both of said first lens and said second lens in the focusing direction; and  
       jog mode adjustment means for driving said second drive means after said focus servo is locked, so as to carry out a jog mode adjustment of the position of said second lens with respect to said first lens.  
     
     
       2. An optical disc recording/reproduction apparatus as claimed in claim  1 , wherein said second lens is arranged so as to oppose said optical disc. 
     
     
       3. An optical disc recording/reproduction apparatus as claimed in claim  1 , said apparatus further comprising detection means for detecting a position of said second lens position with respect to said first lens during said jog mode adjustment. 
     
     
       4. An optical disc recording/reproduction apparatus as claimed in claim  3 , wherein said detection means detects a level of a signal obtained by reproduction of said optical disc during said jog mode adjustment. 
     
     
       5. An optical disc recording/reproduction apparatus as claimed in claim  4 , wherein said signal detected by said detection means is an RF signal or a servo signal. 
     
     
       6. An optical disc recording/reproduction apparatus as claimed in claim  3 , wherein said detection means detects a jitter value during said jog mode adjustment. 
     
     
       7. An optical disc recording/reproduction apparatus as claimed in claim  3 , said apparatus further comprising tracking servo means for tracking said lens group, wherein 
       said detection means detects a position of said second lens with respect to said first lens in a state when said tracking servo is locked.  
     
     
       8. An optical disc recording/reproduction apparatus as claimed in claim  1 , wherein said focus servo means carries out a focus servo by setting in advance for said second drive means a value corresponding to a predetermined position of said second lens with respect to said first lens. 
     
     
       9. An optical disc recording/reproduction apparatus as claimed in claim  1 , wherein said jog mode adjustment means adjusts in jog mode a position of said second lens when said optical disc is mounted. 
     
     
       10. An optical disc recording/reproduction apparatus as claimed in claim  1 , said apparatus further comprising identification means for identifying a type of said disc. 
     
     
       11. An optical disc recording/reproduction apparatus as claimed in claim  1 , wherein said optical disc has a plurality of recording layers and said jog mode adjustment means adjusts in jog mode a position of said second lens with respect to said first lens for each of said recording layers. 
     
     
       12. An optical disc recording/reproduction apparatus as claimed in claim  11 , wherein said focus servo means carries out a focus jump for detecting a second recording layer after detecting a first recording layer of said plurality of recording layers, and 
       said jog mode adjustment means, at said focus jump, sets said second lens at a default position of a recording layer of a jump destination with respect to said first lens.  
     
     
       13. An optical disc recording/reproduction apparatus as claimed in claim  11 , said apparatus further comprising memory means for storing a position of said second lens with respect to said first lens after said jog mode adjustment for each of said recording layers. 
     
     
       14. An optical disc recording/reproduction apparatus for recording or reproducing a data by applying a beam onto an optical disc via a lens group consisting of at least a first lens and a second lens, said method comprising: 
       a focus servo step of simultaneously moving both of said first lens and said second lens in a focusing direction for carrying out a focus servo; and  
       a jog mode adjustment step, after said focus servo is locked, for carrying out a jog mode adjustment of a position of said second lens with respect to said first lens without moving said first lens.  
     
     
       15. An optical disc recording/reproduction apparatus as described in claim  11 , wherein said lens group has a Numerical Aperture (NA) of at least 8. 
     
     
       16. An optical disc recording/reproduction apparatus as described in claim  1 , wherein both first and second lenses are convex lenses.